LISTEN(8) LISTEN(8)
NAME
listen, dkcpu, dkcpunote, dkdiscard, dkecho, dkexportfs,
dkrexexec, dkticket, dkwhoami, dksmtp, dkdcon, dklogin,
dkguard, il7, il9, il565, il566, il17005, il17006, il17007,
il17009, tcp2, tcp7, tcp9, tcp21, tcp23, tcp80, tcp25,
tcp513, tcp515, tcp564, tcp565, tcp566, tcp17007, tcp6000 -
listen for calls on a network device
SYNOPSIS
aux/listen [-q] [-d srvdir] [-t trustsrvdir] [net [name]]
DESCRIPTION
listen announces itself to a network as name (by default the
contents of /env/sysname) and listens for inbound calls to
local services. Net is the network device on which to lis-
ten, by default /net/dk. The services available are exe-
cutable files in srvdir or trustsrvdir. If neither srvdir
nor trustsrvdir is given, listen looks for executable files
in /bin/service. Services found in srvdir are executed as
user none; services found in trustsrvdir as executed as the
user who started listen. Option -q suppresses affirmative
log information.
Service names are made by concatenating the name of the net-
work with the name of the service or port. For example, an
inbound call on the TCP network for port 565 executes ser-
vice tcp565, while a call on the Datakit network for service
whoami executes service dkwhoami.
The following services are available in /bin/service.
dkcpu il17005 server for cpu(1) command.
dkcpunote il17006 /proc/pid/notify forwarding for
cpu(1).
dkexportfs il17007 tcp17007
serve a piece of the name space using
the Plan 9 file system protocol, with
authentication (typically used by
cpu(1)).
tcp564 like 17007, without authentication
(used by Unix systems to see Plan 9
files).
dkrexexec il17009 remote execution.
dkwhoami il565 tcp565 report the address of the incoming
call.
tcp21 FTP daemon
tcp80 HTTP daemon; see httpd(8).
tcp515 LP daemon; see lp(8).
tcp6000 X-window callback
dksmtp tcp25 mail delivery.
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LISTEN(8) LISTEN(8)
dkdcon research Unix terminal connection.
dklogin generic terminal connection.
tcp23 telnet terminal connection.
tcp513 rlogin terminal connection.
tcp2 hold the connection open; sleep for a
long time
dkecho il7 tcp7 echo any bytes received (bit mirror)
dkdiscard il9 tcp9 consume any bytes received (bit
bucket)
The following services are available in /bin/service.auth.
dkguard tcp566 check a SecureNet box.
dkticket il566 authentication requests.
FILES
/net/dk by convention, Datakit device bind point
/net/il by convention, IL device bind point
/net/tcp by convention, TCP device bind point
/env/sysname default announced name
SOURCE
The source to listen is in /sys/src/cmd/aux/listen.c. The
other commands are rc(1) scripts in /rc/bin/service.
SEE ALSO
dkconfig(8), auth(6), dk(3), dial(2)
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